Presser-foot attachment for sewing-machines.



G. S. HERFURTH. PRESSER FOOT ATTACHMENT FOR SEWING MACHINES.

APPLICATION FILED 11011.21, 1910.

991,986, Patented May 9, 1911.

WITNESSES: NVENTOR Q By @Z W %ff# w UNITED STATES PATENT OFFICE.

GEORGE S. HERFURTH, OF WASHINGTON, DISTRICT OF COLUMBIA.

PRESSER-FOOT ATTACHMENT FOR SEWING-MACHINES.

To all whom it may concern:

Be it known that I, GEORGE S. I'IERFURTH, a citizen of the UnitedStates, residing at Washington, in the District of Columbia, haveinvented certain new and useful Imrovements in Presser-Foot Attachmentsfor bewing-Machines, of which the following is a specification.

The present invention comprises a novel attachment designed to beapplied to the cam lever ordinarily provided on certain types of sewingmachines for quickly raising and lowering the presser foot of themachine with respect to the goods ordinarily engaged thereby. Theattachment affords an auxiliary means for controlling the adjustment ofthe presser foot and one which is adapted to be rendered inoperative oroperative with respect to the cam lever by reason of the arrangement ofthe latter upon the head of the machine.

In the operation of sewing machines much difficulty is experienced bythe lack of conveniently operable means for adjusting the pressure ofthe presser foot, when goods of difl'erent thicknesses, or the like, arebeing stitched. For instance, when the operator finds it necessary tostitch goods somewhat thicker than those previously sewed, it isdesirable that the tension or pressure exerted by the presser footagainst the goods should be slightly relieved, at the same time beingsufficient to secure proper feeding of the goods by the feed plate. Theabove control of the pressure of the resser foot is ob tained by thepresent lnvention. Again, when stitching together goods having unusuallysmooth surfaces, such for instance, as velvet, or goods having a roughsurface, as when stitching lining on goods having a smooth surface, itis usual that the feed plate causes the material at the bottom to feedfaster than that being stitched thereto which is retarded by the tensionof the presser foot. Still another purpose is subserved by theattachment; namely, when attaching linings or stiffening means tomaterials, it is found necessary to run the lines of stitching back andforth in a zig-zag manner, and to accomplish this, the operatorsometimes holds the lifter lever slightly raised to partially relievethe tension on the goods. This latter operation prevents the use of bothhands of the operator in manipulating the goods, and furthermore, anaccurate or positive adjustment by manual efforts is impossible.

Specification of Letters Patent.

Application filed November 21, 1910.

Patented May 9, 1911.

Serial No. 593,563.

For a full comprehension of the advan tages and construction of thisinvention, reference is to be had to the accompanying drawings, inwhich- Figure 1 is an end view of a sewing machine head with the endplate partly broken away, showing the attachment applied to the lifterlever; and Fig. 2 is a modification of the invention.

Referring more particularly to the drawings, A is the end plate of thesupporting head of a sewing machine.

B is a lifter lever pivoted at C, having the usual cam D thereon adaptedto engage the guide bracket E on the foot bar E, whereby the latter israised when it is desired to remove goods from beneath the presser footF of the machine. The lifter lever B has a threaded openin therein inwhich is adapted to be screwed the adjusting screw G, by which auxiliarymeans the desired adjustment of the tension of the presser foot isaccomplished, when the said lifter lever is lowered for operation, theadjusting screw engaging with the supporting head of the machine.

It will be readily apparent that when it is desired to stitch goodsthicker than the ordinary materials for which the machine is positivelyadjusted by the tap H, on the foot bar IE, it is only necessary, afterlowering the lifter lever, to turn the adjusting screw, thereby raisingthe presser foot to any de sirable adjustment with res not to the feedplate of the machine. In t is manner, the tension is increased ordiminished by screwing the adjusting screw out or in, as need be,allowing the free use of both hands of the operator for moving the goodsin any desirable direction under the presser foot.

It will be observed that the lifter lever B which is an ordinary camlever coacting with the bracket E, extends through a slot in a side ofthe head A and the lower end of the slot limits the downward movement ofthe lifter lever. The arrangement of the screw Gr upon the lifter lever,and the mounting of the latter upon the head A are especiallyadvantageous in that the screw G may be rendered inoperative to affordauxiliary adjusting means for the presser foot at the will of theoperator. In other Words, if it is desired that the presser foot F beused in the customary way, the particular work not requiring theauxiliary adjustment afforded by the screw Gr, the latter may be turnedso as to unscrew with respect to the lever B until the innermost end ofthe screw is clear of the head A when the lever B is moved downwardly toengage the lower end of the slot of the head A through which it passes.Furthermore, by reason of the mounting of the screw G upon the lever B,when the latter is thrown upwardly the screw G will be carried upwardlywith the lever B and supported by the lever in an inoperative positlon.

In the modified form illustrated in Fig. 2, the adjusting screw G isprovided with a hexagonal or many sided shoulder I, having a flat orleaf spring J, attached to the lifter lever at one end, and adapted toengage the said shoulder at the other end, to prevent the vibration ofthe machine from turning said adjusting screw, when unauthorized, duringoperation.

This invention appertains particularly to that class of sewing machinesemploying a vertically movable foot bar supporting the presser foot,said foot bar being controlled in its raising and lowering movements bya cam of the type set forth.

Having thus fully described the invention, what is claimed as new is 1.In combination, a sewing machine head provided with a slot in asidethereof, a foot bar mounted for vertical reciprocating move- 'ment insaid head, a presser foot carried by said foot bar, spring meansnormally coacting with the foot bar to force the presser footdownwardly, a lifter lever pivoted at one end in the head and coactingto control the raising and lowering movement of the foot bar andextending through the slot in the head, means whereby said lifter lever,in coacting with the foot bar may be held at the upper or lower limitsof its movement, and an adjusting screw mounted on the outer end portionof the litter lever and arranged to engage the head when the lifterleveris moved downwardly toward its lower limit of movement, whereby tosecure an auxiliary ad ustment of the presser foot, sald screw beingadapted to be carried into an inoperative position when the lifter leveris raised to lift the presser foot.

2. In combination, a sewing machine head, a foot bar movably mountedthereon, a presser foot carried by said bar, spring means normallytending to move said foot bar and presser foot downwardly, a lifterlever on the head movable so as to remain in raised or lowered positionsto effect corresponding adjustment of the foot bar, and an Copies ofthis patent may be obtained for five cents each, by addressing theCommissioner of Patents. Washington, D. G.

